https://prism-break.org/en/categories/bsd/#web-browser-addons

Don't trust disconnect instead do some about:config and option editing

Also please don't use google as your search egnine.

https://github.com/asciimoo/searx/wiki/Searx-instances

also some of these are good too http://www.logicalincrements.com/firefox/

If you got google maps on your phone it also collects your location

Every single one of those is true. All of them can be disabled (autocomplete, prefetching, whitelisting, phising protection) but are enabled by default. Firefox also has some of these 'features' and they can also be disabled.

If you want to truly be scared: most of this doesn't matter because websites can uniquely identify your browser anyways ( EFF link ). There are also service based cookies (gmail, facebook, etc.). This means that any website running google analytics or advertising (most of them) could theoretically uniquely identify you and keep a history of your browsing. Facebook does the same thing using the 'like' buttons embedded in webpages. Extensions such as ghostery and ublock can limit this.

There are also many cookie like tracking mechanisms used ( EFF link 2 ) that aren't necessarily controlled by the browser and are very hard to control.

Edit: clickable links.

Edit2: a somewhat date guide to securing your browser Yet another EFF link .

The links you type on Firefox are also sent to Google unless you disable safe browsing.

I can tell you that Chrome can run a lot of instances of what looks like itself on a Windows 7 PC. You have to the Processes tab of your Task Manager to see them, and this happens whether you are running it or not. I don't have the skills to verify anything on this list (other than Chrome syncs across all of your devices if you sign in, but that's an advertised feature), but based on my observation of Chrome's behaviour it wouldn't surprise me.